The objectives of this study are to: (1) determine the maximum tolerated dose of tecogalan administered twice weekly for 21 days; (2) determine the qualitative and quantitative toxicities of tecogalan on this schedule; (3) determine the appropriate dose of tecogalan on this schedule for Phase II trials; (4) characterize the pharmacokinetics/pharmacodynamics of tecogalan; and (5) collect information about antitumor effects of this drug.